1. Field of the Invention
The present invention relates to graph generating devices which automatically generate a graph based on given data and more particularly to a graph generating device capable of changing graph elements at moved positions when data corresponding to the graph elements are updated after the graph elements are moved to desired positions.
2. Description of the Related Art
A conventional graph generating device is capable of generating predetermined kinds of graphs. When a data is given, the graph generating device generates a graph corresponding to the given data. For example, a device having a function of generating a bar graph, generates and displays a bar graph such as shown in FIG. 32 when data A1, B1 and C1 are given corresponding to bars (graph element) which constitute the bar graph.
Some conventional devices may also have the function of editing the graph thus generated. With these devices, the bars a, b and c of the bar graph shown in FIG. 32 can be laid out and displayed on, for example, a map of Japan as shown in FIG. 33.
In these conventional device, however, the bars a, b and c are only moved or copied to desired positions in the editing operation. Thus, when the data A1, B1 and C1 are changed or updated, these data must be changed in the bar graph of FIG. 32 and then the resulting new bars a, b and c are laid out on the map shown in FIG. 33.
A device has been proposed which is capable of moving a graph element freely to any position (published unexamined Japanese patent application Hei 3-74783). However, this device only moves, for example, the label of a graph and therefore cannot update graph data while displaying graph elements corresponding to the data at any position on the display unit.
As described above, these conventional graph generating devices can move the displayed graph elements to desired positions. However, each time data for the graph elements are updated, it is necessary to generated a graph according to the updated data and then again layout the graph elements to desired positions.